1. Field of the Invention
The present invention relates to a data driver, an organic light emitting display device using the same, and a method of driving the organic light emitting display device, and more particularly to, a data driver capable of displaying images with a substantially uniform brightness, an organic light emitting display device using the same, and a method of driving the organic light emitting display device.
2. Discussion of Related Art
Recently, various types of flat panel displays (FPDs) have been developed that reduced weight and volume compared to cathode ray tubes (CRT). The FPDs include liquid crystal displays (LCDs), field emission displays (FEDs), plasma display panels (PDPs), and organic light emitting display devices.
Among the FPDs, the organic light emitting display devices display images using organic light emitting diode devices that generate light by re-combination of electrons and holes. The organic light emitting display device has high response speed and is driven with low power consumption.
FIG. 1 illustrates the structure of a conventional organic light emitting display device.
Referring to FIG. 1, the conventional organic light emitting display device includes a display region 30 including a plurality of pixels 40 coupled to scan lines S1 to Sn and data lines D1 to Dm, a scan driver 10 for driving the scan lines S1 to Sn, a data driver 20 for driving the data lines D1 to Dm, and a timing controller 50 for controlling the scan driver 10 and the data driver 20.
The timing controller 50 generates data driving control signals DCS and scan driving control signals SCS in response to synchronizing signals supplied from the outside. The data driving control signals DCS generated by the timing controller 50 are supplied to the data driver 20 and the scan driving control signals SCS generated by the timing controller 50 are supplied to the scan driver 10. The timing controller 50 supplies the data Data supplied from the outside to the data driver 20.
The scan driver 10 receives the scan driving control signals SCS from the timing controller 50. The scan driver 10 then generates the scan signals to sequentially supply the generated scan signals to the scan lines S1 to Sn.
The data driver 20 receives the data driving control signals DCS from the timing controller 50. The data driver 20 then generates data signals and supplies the generated data signals to the data lines D1 to Dm in synchronization with the scan signals.
The display region 30 receives first and second power from a first power source ELVDD and a second power source ELVSS from the outside, respectively, and supplies the first and second power to the pixels 40. The pixels 40 then control the currents that flow from the first power source ELVDD to the second power source ELVSS via an organic light emitting diode devices in response to the data signals to generate light components corresponding to the data signals.
That is, according to the conventional organic light emitting display device, each of the pixels 40 generates light with predetermined brightness in response to each of the data signals. However, according to the conventional organic light emitting display device, due to non-uniformity in the threshold voltages of transistors included in the pixels 40 and deviation in electron mobility, it may not be possible to display images with desired brightness. While the threshold voltages of the transistors included in the pixels 40 may be compensated for by controlling the structure of the pixel circuits included in the pixels 40, the deviation in the electron mobility is not compensated for. Therefore, an organic light emitting display device capable of displaying images with a substantially uniform brightness regardless of the deviation in the electron mobility is desired.